FUINDAMENTALS DEVELOPMENT FOR COMPUTATION OF SCREW SCREENS FOR BULK MATERIAL SEPARATION AND EXPERIENCE OF THEIR INTRODUCTION TO PRODUCTION

2021 ◽  
Vol 2021 (4) ◽  
pp. 4-17
Author(s):  
Aleksandr Sekisov ◽  
Evgeniya Belokur ◽  
Georgiy Serga
Keyword(s):  
Bulk Material ◽  
Test Sample ◽  
Experimental Investigations ◽  
Test Plant ◽  
Complex Method ◽  
Longitudinal Motion ◽  
Working Chamber ◽  
Bulk Medium ◽  
Material Separation ◽  
Movement Parameters

The work purpose is to increase productivity in bulk material separation by means of the development of a test sample of the installation for bulk material separation into fractions. There is considered bulk material motion in a working chamber of the screw screen and the results of experimental investigations of bulk medium movement parameters are presented, depending on design and operation characteristics of screw screens, and also nomograms of dependences of a rate of bulk particle longitudinal movements upon a screw screen diameter, for different values of correction factors, weight of bulk particles, an angular velocity of the screw screen and fill factors. A design of the plant for bulk separation, test data and technical characteristics of the test plant are shown. A novelty is confirmed by six invention patents of the RF. By means of the complex method of investigations there are obtained dependences for definition of a rate of bulk particle longitudinal motion in screw screens, and also a length of working chamber of the screw screen.

INVESTIGATION OF BULK MATERIAL MOTION IN SPIRAL SIEVES

2021 ◽  
Vol 2021 (2) ◽  
pp. 4-12
Author(s):  
Evgeniya Belokur ◽  
Aleksandr Sekisov ◽  
Georgiy Serga
Keyword(s):  
Mathematical Model ◽  
Process Development ◽  
Bulk Material ◽  
Experimental Investigations ◽  
Complex Method ◽  
Longitudinal Motion ◽  
Experimental Plant ◽  
Model Choice ◽  
Material Particle ◽  
Material Separation

The work purpose is to increase the productivity of bulk material separation by means of engineering process development based on fundamentally new engineering equipment in the form of spiral sieves, the novelty of which is confirmed by six patents for invention of the Russian Federation. In the work there was used a complex method of investigations. Analytical methods allowed offering dependences for the definition of bulk material longitudinal motion speed in spiral sieves. Experimental investigations were carried out in order to confirm analytical dependences. The analytical investigation of bulk material separation into fractions for the purpose of conditional model choice for its description is presented. A mathematical model choice is fulfilled. There is analyzed a model of continuous medium and that of a material particle. A mathematical model is developed to determine a speed of longitudinal motion of bulk material from charging to unloading. There is presented not only a circuit and an experimental plant created in metal version, but the results of experimental investigations of bulk medium motion parameters subject to spiral sieve design peculiarities are shown which presented a coincidence level high enough.

Контроль электрофизических параметров метаматериалов методом поверхностных электромагнитных волн

2021 ◽  
pp. 51-67
Author(s):  
А.И. Казьмин ◽  
П.А. Федюнин
Keyword(s):  
Inverse Problem ◽  
Electromagnetic Wave ◽  
Radio Wave ◽  
Local Control ◽  
Negative Refraction ◽  
Test Sample ◽  
Experimental Investigations ◽  
Surface Electromagnetic Wave ◽  
New Radio ◽  
Electrophysical Parameters

Development of metamaterials has led to the search and choice of effective methods of radio-wave nondestructive testing of their electrophysical parameters. The existing approaches to testing based on extracted of effective electrophysical parameters of metamaterials from the coefficients of reflection and transmission of an electromagnetic wave have low reliability and don't provide their local control. We present the new radio-wave method of local control of complex dielectric permittivity and magnetic permeability, as well as the thickness of metamaterial plate on a metal substrate with surface microwaves. The method is based on the solution of inverse problem in the determination of effective electrophysical parameters of metamaterial from the frequency dependence of the attenuation coefficient of the field of a slow surface electromagnetic wave excited in a test sample. The electrophysical parameters of the metamaterial are represented as parametric frequency functions in accordance with the Drude-Lorentz models of dispersion, and the solution of the inverse problem is reduced to minimizing the objective function constructed based on the discrepancy between the experimental and design theoretical values of the attenuation coefficients of surface electromagnetic wave fields on a grid of discrete frequencies. The structure of a measuring complex that implements the proposed method of control is proposed. For the numerical and experimental verification of the method, a sample of a metamaterial plate based on SRR elements with a negative refraction region in the frequency band 10.06–10.64 GHz was investigated. Experimental investigations of the metamaterial demonstrated the theoretical capabilities gained with measurement of the local electrophysical parameters with relative error not greater 10 %.

scholarly journals FP-TES: Fluidization Based Particle Thermal Energy Storage, Part II: Experimental Investigations

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4302
Author(s):  
Verena Sulzgruber ◽  
David Wünsch ◽  
Heimo Walter ◽  
Markus Haider
Keyword(s):  
Experimental Study ◽  
Energy Storage ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Bulk Material ◽  
Storage System ◽  
Co2 Reduction ◽  
Cold Test ◽  
Experimental Investigations ◽  
Mathematical Correlation

In recent years, the fight against global warming and therefore CO2 reduction have become the most important issue for humanity. As a result, volatile sources of energy—like wind and solar power—are penetrating the electrical grid and therefore an increased demand on storage capacities is required. At the TU Wien Institute for Energy Systems and Thermodynamics, a Fluidization Based Particle Thermal Energy Storage (FP-TES) working with bulk material as a sensible storage material is developed. In this paper, the concept and an experimental study of the cold test rig is presented. By means of various pressure measurements, a novel concept of particle transport based on advanced fluidization technology without any mechanical transport devices is investigated. Moreover, a mathematical correlation between the pressure gradients and the particle mass flow is found. Overall, the experimental study provides a full proof of concept and functionality of the novel energy storage system.

scholarly journals INDIVIDUAL ROCKS SEGMENTATION IN TERRESTRIAL LASER SCANNING POINT CLOUD USING ITERATIVE DBSCAN ALGORITHM

2018 ◽  
Vol XLII-2 ◽  
pp. 1157-1161
Author(s):  
A. Walicka ◽  
G. Jóźków ◽  
A. Borkowski
Keyword(s):  
Point Cloud ◽  
Laser Scanning ◽  
Automatic Segmentation ◽  
Terrestrial Laser Scanning ◽  
Principal Component ◽  
Test Sample ◽  
Dbscan Algorithm ◽  
Fluvial Transport ◽  
River Bed ◽  
Movement Parameters

The fluvial transport is an important aspect of hydrological and geomorphologic studies. The knowledge about the movement parameters of different-size fractions is essential in many applications, such as the exploration of the watercourse changes, the calculation of the river bed parameters or the investigation of the frequency and the nature of the weather events. Traditional techniques used for the fluvial transport investigations do not provide any information about the long-term horizontal movement of the rocks. This information can be gained by means of terrestrial laser scanning (TLS). However, this is a complex issue consisting of several stages of data processing. In this study the methodology for individual rocks segmentation from TLS point cloud has been proposed, which is the first step for the semi-automatic algorithm for movement detection of individual rocks. The proposed algorithm is executed in two steps. Firstly, the point cloud is classified as rocks or background using only geometrical information. Secondly, the DBSCAN algorithm is executed iteratively on points classified as rocks until only one stone is detected in each segment. The number of rocks in each segment is determined using principal component analysis (PCA) and simple derivative method for peak detection. As a result, several segments that correspond to individual rocks are formed. Numerical tests were executed on two test samples. The results of the semi-automatic segmentation were compared to results acquired by manual segmentation. The proposed methodology enabled to successfully segment 76 % and 72 % of rocks in the test sample 1 and test sample 2, respectively.

The Investigations of Tool Wear and Wear Mechanism with Water Vapor as Coolants and Lubricants in Green Cutting

2007 ◽  
Vol 10-12 ◽  
pp. 913-917 ◽  
Author(s):  
Jun Yan Liu ◽  
Rong Di Han ◽  
Yang Wang
Keyword(s):  
Water Vapor ◽  
Tool Wear ◽  
Tool Life ◽  
Bulk Material ◽  
Contact Region ◽  
Cutting Fluid ◽  
304 Stainless Steel ◽  
Experimental Investigations ◽  
Cemented Carbide Tool ◽  
Increase Productivity

In machining, coolants and lubricants improve machinability, increase productivity by reducing the tool wear and extend the tool life. However, the use of cutting fluid in metal working may seriously degrade the quality of environment. Green cutting is becoming increasingly more popular due to concern regarding the safety of the environment and operator health. The experimental investigations were carried out with cemented carbide tool in turning ANSI 304 stainless steel and applications of water vapor, CO2, O2 as coolants and lubricants. The application of water vapor as coolants and lubricants allowed extending tool life. The catalysis chemical reaction have been generated between water molecules (H2O), oxygen atoms (O) of water vapor and fresh metal surface of tool-chip contact region, and multi-dimension metal oxidations which has been formed in tool-chip contact zone weakened mutual action between tool bulk material and chip.

Experimental Investigations on the Critical Vortex Dynamics with Controlled Disorder

1999 ◽  
Vol 13 (09n10) ◽  
pp. 1137-1142
Author(s):  
E. Crescio ◽  
R. Gerbaldo ◽  
G. Ghigo ◽  
L. Gozzelino ◽  
E. Mezzetti ◽  
...  
Keyword(s):  
Bulk Material ◽  
Total Sample ◽  
Dose Dependence ◽  
Experimental Investigations ◽  
Superconducting Properties ◽  
Dose Equivalent ◽  
Implantation Depth ◽  
Experimental Findings ◽  
Equivalent Field ◽  
Nanometric Size

The possibility to enhance in a predictable way the superconducting properties behavior of a bulk material by introducing linearly correlated defects within a surface layer has been demonstrated. Ag/BSCCO-2223 tapes were irradiated by means of 0.25 GeV Au ions at different fluences, with a dose equivalent field B ϕ ranging from 1 T to 5 T. The implantation depth was about 15 μm corresponding to about 15% of the total sample thickness. Sample independent enhancements of different a.c and d.c properties show up, due to vortex confinement in the whole sample. The sample independence exhibited by all the experimental findings as well as, on the other side, the dose dependence of the enhancements, allow to design in advance the performances of a monofilamentary tape where defect trenches of nanometric size are scratched.

Some Studies on Life Prediction of Thermal Sprayed Coatings Under Rolling Contact Conditions

1999 ◽  
Vol 122 (3) ◽  
pp. 503-510 ◽  
Author(s):  
B. Y. Sarma ◽  
M. M. Mayuram
Keyword(s):  
Contact Stress ◽  
Layered Structure ◽  
Life Prediction ◽  
Prediction Models ◽  
Bulk Material ◽  
Experimental Testing ◽  
Rolling Contact ◽  
Experimental Investigations ◽  
Sprayed Coatings ◽  
Thermal Sprayed Coatings

Design of engineering components is concerned with their strength and durability characteristics. While design for strength is influenced by the bulk material characteristics, the design for durability is dependant on the surface characteristics. Majority of the component failures are surface originated. Surface engineering could play a vital role in minimizing such failures. Thermal sprayed coatings, one of the versatile surface coating techniques, can be applied to components of machinery surfaces to avoid such failures. The present paper presents a methodology for contact stress evaluation of surface coated elements, adopting a layered structure approach, and thereby analytically predict their spalling life. Further data on cycles to single pit formation, and spalling of spray fused coatings obtained from experimental testing are presented for assessing the applicability of life prediction models to layered structures such as sprayed coatings. Experimental investigations were conducted on spray fused coatings using a twin disk RCF test setup. The surface and subsurface contact stress distribution have been obtained analytically by Smith–Liu equations along with first order model perturbation method (FOMP), to account for the variation of elastic modulus constants of the layered structure. Applying Lundberg-Palmgren and Tallian life prediction models, the spalling life of these coatings has been predicted analytically and compared with experimental life values. [S0742-4787(00)02502-9]

scholarly journals Determination of Curcuminoids in Turmeric Dietary Supplements by HPLC-DAD: Multi-laboratory Study Through the NIH-ODS/NIST Quality Assurance Program

2020 ◽  
Vol 103 (6) ◽  
pp. 1625-1632
Author(s):  
Elizabeth M Mudge ◽  
Paula N Brown ◽  
Catherine A Rimmer ◽  
Melissa M Phillips
Keyword(s):  
Quality Assurance ◽  
Dietary Supplements ◽  
Laboratory Study ◽  
Bulk Material ◽  
Test Sample ◽  
National Institutes Of Health ◽  
Quality Assurance Program ◽  
Quality Markers ◽  
Repeatability And Reproducibility

Abstract Background Turmeric is a medicinal herb containing curcuminoids, used as quality markers in dietary supplements. In 2016, an AOAC First Action Official MethodSM was adopted for quantitation of curcuminoids and requires multi-laboratory reproducibility data for Final Action status. Objective To collect reproducibility data for the quantitation of curcuminoids in dietary supplements through the National Institutes of Health Office of Dietary Supplements/National Institute of Standards and Technology Quality Assurance Program (QAP). Method Laboratories that participated in the QAP by following the Official Methods of AnalysisSM Method 2016.16, submitted data for ten turmeric products. The data were analyzed for mean, repeatability, and reproducibility standard deviations, repeatability, and reproducibility. Results The initial data collection resulted in insufficient replicates (five) for each test sample to determine reproducibility, therefore laboratories were provided additional materials resulting in an incremental data approach. For homogenous products, reproducibility for curcumin ranged from 3.4 to 10.3%, bisdemethoxycurcumin with reproducibility ranging from 6.4 to 14.8%, and demethoxycurcumin ranging from 5.6 to 9.9%. The method was unsuitable for the quantitation of curcuminoids in complex smoothie products, products containing microbeads, or tinctures based on interlaboratory variances. Recommendations were provided for future multi-laboratory studies performed through QAPs and incremental approaches. Conclusions Method 2016.16 is suitable for the quantitation of curcuminoids and should be adopted for Final Action status for single and multi-ingredient dietary supplements containing dried roots, dried powders/extracts in bulk material, capsules, and softgels. Highlights Reproducibility for Method 2016.16 was collected through a non-traditional incremental data multi-laboratory study. The method is suitable for quantitation of curcuminoids in most common dietary supplements.

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